Imagine for a moment that you had one of these retro-cool turnkey doorbells installed in your place. How many people do you think would have no idea how to use it or for that matter, even know what it was? I can see it now, "look at this guy, his deadbolt was installed the wrong way!"
This is really what used to be a corridor bell, as it was originally used for flats in apartment blocks. But the neat bell mechanism, made completely without the use of plastic components, can also be heard in the average-sized family house. The key twist mechanism is designed to fit doors of 6 cm thickness, but can be shortened for thinner doors by cutting the square shaft with a hacksaw. The quality nickel-coated steel plate bell can also be mounted outside.
Link: Manufactum
Via: The Red Ferret Journal